Deadly Bacteria Lurk In Deepwater Horizon Tar Balls

Nearly two years after the Deepwater Horizon disaster gushed millions of barrels of oil into the Gulf of Mexico, tar balls from the spill are still turning up on Alabama’s shores after storms. One researcher has recommended that folks steer clear of these tar balls after studies find them “chock-full of potentially deadly bacteria.”

In research published online November 2011 in the journal EcoHealth, Auburn University microbiologist Cova Arias and colleagues discovered that Deepwater Horizon tar balls found months after the spill contained high levels of bacteria, including 10 times the level of Vibrio vulnificus as found in the surrounding sand. This finding was first reported by the Associated Press. For the uninformed, V. vulnificus is the leading cause of seafood-borne disease fatalities nationwide. It has a fatality rate of 20 to 30 percent when it infects skin wounds. Dr. Arias says:

We don’t know what the real risk is at this point. But to be safe, beachgoers should avoid handling the tar balls.

We have to remember that about 5 million barrels of oil (205 million gallons), spilled from a riser pipe in the seafloor after the Deepwater Horizon rig exploded and sank in late April 2010. Some of that oil persists in the Gulf in the form of tar balls. Dr. Arias and her colleagues collected tar balls from beaches in Alabama and Mississippi from July through October 2010, shortly after the spill was capped. They found between 20 and 40 tar balls per about every 11 square feet, with each tar ball about 1.2 inches across. The team also collected sand and water samples.

Analyses of these samples showed a surprisingly high number of total bacteria in the tar balls — between 5.1 million and 8.3 million colony-forming units per gram, much higher than in sand or seawater. Most alarmingly, V. vulnificus numbers in tar balls were 10 times that in nearby sand and 100 times higher than numbers in seawater samples. Dr. Arias said the finding was surprising, but that it makes sense that bacteria would thrive in carbon-rich tar balls. She added that the V. vulnificus live off the byproducts of other carbon-eating bacteria in these oily chunks. Obviously, this is a most serious problem and one that can’t be ignored. If you need more information on this matter, contact Sandra Walters in our Toxic Torts Section at 800-898-2034 or by email at Sandra.Walters@beasleyallen.com and she will have one of our lawyers in the Section respond.